Tubular spreaders are used to create precise spaces for shuttering in the thickness of the concrete wall to be erected. The through ties of the spreaders using a shuttering anchor provide the economic advantage of recovering anchor materials. The spacer tubes in fibrous concrete, plastic or steel are complemented by a number of cones and different accessories. This ensures that once shuttering is completed, the cone cavities are filled with mortar or stoppers in fair-faced concrete quality.